Controlling a surgical instrument

Abstract

A control system for regulating operative control of a surgical instrument by a remote surgeon input device. The surgical instrument is supported by an articulated robot arm, and comprises an end effector connected to a shaft by an articulated coupling. The remote surgeon input device is capable of operatively controlling the surgical instrument by controlling articulation of the end effector, and controlling articulation of the robot arm and coupling. On receiving a request to engage operative control of the surgical instrument by the surgeon input device, the control system initially engages operative control of articulation of the robot arm and coupling by the surgeon input device, whilst maintaining disengagement of operative control of articulation of the end effector by the surgeon input device. Subsequently, the control system engages operative control of articulation of the end effector by the surgeon input device following a manipulation of the surgeon input device.

The invention claimed is: 
     
       1. A control system configured to regulate operative control of a surgical instrument by a remote surgeon input device, the surgical instrument being supported by an articulated robot arm, the surgical instrument comprising an end effector connected to a shaft by an articulated coupling, the remote surgeon input device capable of operatively controlling the surgical instrument by (i) controlling articulation of the end effector, and (ii) controlling articulation of the robot arm and the coupling, the control system comprising a processor and a memory, wherein the control system is configured to:
 on receiving a request to engage operative control of the surgical instrument by the surgeon input device: 
 initially engage operative control of articulation of the robot arm and the coupling by the surgeon input device, whilst maintaining disengagement of operative control of articulation of the end effector by the surgeon input device, such that inputs received from the surgeon input device can cause articulation of the robot arm and the coupling but cannot cause articulation of the end effector; and 
 subsequently engage operative control of articulation of the end effector by the surgeon input device following a manipulation of the surgeon input device to a required configuration. 
 
     
     
       2. A control system as claimed in  claim 1 , wherein the surgeon input device comprises an articulated component which is manipulatable to operatively control articulation of the end effector, wherein the control system is configured to only engage operative control of the articulated component to the end effector when the articulated component is manipulated such that the configuration of the articulated component matches the configuration of the end effector. 
     
     
       3. A control system as claimed in  claim 2 , configured to control an actuator to drive the configuration of the articulated component towards the configuration of the end effector. 
     
     
       4. A control system as claimed in  claim 2 , wherein the end effector comprises a pair of end effector elements rotatable relative to each other and separated by an end effector angle, and the articulated component of the surgeon input device comprises a pincer element rotatable relative to another portion of the surgeon input device and separated from that other portion of the surgeon input device by a pincer angle, the pincer element configured to control rotation of the end effector elements to a separation of a drive angle, the drive angle being a function of the pincer angle, the control system configured to:
 receive an indication of the end effector angle; 
 receive an indication of the drive angle; and 
 engage operative control of opening and closing of the end effector elements by the pincer element when the drive angle matches the end effector angle. 
 
     
     
       5. A control system as claimed in  claim 4 , wherein the control system is configured to engage operative control of opening and closing of the end effector elements by the pincer element following:
 (i) opening the pincer element relative to the other portion of the surgeon input device such that the drive angle exceeds the end effector angle, and then 
 (ii) closing the pincer element relative to the other portion of the surgeon input device until the drive angle matches the end effector angle. 
 
     
     
       6. A control system as claimed in  claim 5 , only configured to engage operative control of opening and closing of the end effector elements by the pincer element following: (i) opening the pincer element relative to the other portion of the surgeon input device to their maximum separation angle, and (ii) closing the pincer element relative to the other portion of the surgeon input device until the drive angle matches the end effector angle. 
     
     
       7. A control system as claimed in  claim 6 , configured to:
 store the end effector angle from the received indication; 
 on receiving the request to engage operative control of the surgical instrument by the surgeon input device, periodically receive an indication of the drive angle; 
 compare the drive angle from the most recent periodically received indication to the stored end effector angle; and 
 determine a match when the compared drive angle is the same as the stored end effector angle. 
 
     
     
       8. A control system as claimed in  claim 7 , configured to only compare the drive angle from the most recent periodically received indication to the stored end effector angle following detection that the pincer element and other portion of the surgeon input device have been opened to their maximum separation angle. 
     
     
       9. A control system as claimed in  claim 5 , configured to, when the pincer element is being closed relative to the other portion of the surgeon input device, when the drive angle exceeds the end effector angle by less than a predetermined offset, control an actuator to drive the pincer element towards the other portion of the surgeon input device until the drive angle matches the end effector angle. 
     
     
       10. A control system as claimed in  claim 4 , wherein the drive angle is the pincer angle. 
     
     
       11. A control system as claimed in  claim 4 , wherein the other portion of the surgeon input device is a body of the surgeon input device. 
     
     
       12. A control system as claimed in  claim 4 , wherein the other portion of the surgeon input device is a further pincer element. 
     
     
       13. A control system as claimed in  claim 1 , configured to, on engaging operative control of articulation of the end effector by the surgeon input device, control the surgeon input device to generate a haptic indication to a user of the surgeon input device. 
     
     
       14. A control system as claimed in  claim 1 , configured to, on engaging operative control of articulation of the end effector by the surgeon input device, enable force feedback from the surgical robotic instrument to the surgeon input device.